The emission of which of the following gases into the atmosphere reduces global warming?

Correct option is D

Answer: (d) Oxygen
Explanation: Oxygen does not contribute to global warming and is essential for life on Earth. Unlike greenhouse gases such as carbon dioxide (CO₂), carbon monoxide (CO), and hydrogen sulfide (H₂S), oxygen (O₂) does not trap heat in the atmosphere. Instead, increased oxygen levels support photosynthesis, a process in which plants absorb CO₂ and release O₂, helping to mitigate global warming.
Other Options Explained:
· (a) Carbon dioxide (CO₂): A major greenhouse gas that traps heat and contributes to global warming.
· (b) Carbon monoxide (CO): Although not a strong greenhouse gas itself, it contributes indirectly by reacting with hydroxyl radicals, reducing the atmosphere’s ability to break down methane (another potent greenhouse gas).
· (c) Hydrogen sulfide (H₂S): A gas with a foul odor, produced from natural sources and industrial activities, which can contribute to atmospheric pollution but does not significantly impact global warming.
Thus, oxygen (O₂) is the correct answer, as its presence does not contribute to climate change and supports processes that help reduce greenhouse gas levels.